1. Field of the Invention
The present invention relates to a control system for controlling actions of a machine, and more specifically, to controlling actions of the machine according to the luminance of environmental light and the distance between the machine and a user.
2. Description of the Prior Art
Robots often contain a display unit such as a liquid crystal display (LCD) or one or more light emitting diodes (LEDs) for expressing its current state to the user of the robot. In addition, robots can also use movement to indicate their mood or their status to the user. The user can recognize these actions, and thereby know how he should interact with the robot. Each action performed by the robot requires some source of power, such as battery power. However, if the robot is programmed to perform the same actions in all situations, more power is consumed since the robot cannot utilize any kind of power saving mode.